Growing clinical evidence-base highlights long-term side effects and risks associated with the most popular prostate cancer treatments
There is currently no consensus as to the optimal treatment for localised prostate cancer, and urologists and radiation oncologists continue to debate the relative merits of therapies. Most men and their partners ultimately choose a therapy based on how well informed they are about the various options, their respective side effect profiles and personal lifestyle choices, and recommendation from their consultant.
Yet, for many men, this is a confusing and worrying time. Men diagnosed with localised prostate cancer have numerous management options, including active surveillance, androgen-deprivation (hormone) therapy, and definitive therapy with the intent to eradicate or cure the cancer.
Among patients who are offered these curative-intent treatments, the vast majority are offered either radical prostatectomy (surgery to remove the prostate) or radiation therapy. Radiation therapy, however, includes a range of treatments and dosing including external-beam based therapies, high-dose-rate (HDR) or low-dose- rate (LDR) brachytherapy, and combinations of beam and brachytherapy, with or without hormone therapy. Choosing amongst these can be a daunting task.
However, there is a growing clinical evidence-base which suggests certain standard-practice treatment options and doses may not be as effective, and / or have significant long-term clinical side effects that clinicians and patients alike should be aware of.
Urinary Adverse Events after High- versus Low-Dose-Rate Brachytherapy with or without Radical (External-beam) Radiotherapy
A 2016 study comparing the incidence of severe urinary adverse events (UAEs) after low-dose-rate (LDR) and high-dose-rate (HDR) brachytherapy, as well as after LDR plus external beam radiation therapy (EBRT) and HDR plus EBRT, found no statistically significant toxicity differences were observed between LDR and HDR. However, combination radiation therapy (either HDR plus EBRT or LDR plus EBRT) increases the risk of severe UAEs compared with HDR alone or LDR alone.
Single-dose High-Dose-Rate Brachytherapy
Most recently, a 2021 study by Shreya Armstrong et al of the Mount Vernon Cancer Centre, Northwood, UK, undertook a retrospective review of treatment records of patients who received single-dose (fraction) HDR-B, concluding that long-term follow up of single dose HDR-B for localised prostate cancer has revealed higher than expected rates of biochemical and local failure and should therefore not be used as a monotherapy for intermediate- and high-risk cancer patients.
This is further backed up by a 2019 study from Leeds Teaching Hospitals NHS Trust comparing men with intermediate and high risk prostate cancer treated using LDR–EBRT and HDR–EBRT, which concluded that patients treated with HDR–EBRT were more than twice as likely to experience biochemical progression compared with LDR–EBRT.
Moreover, recent advances in the development of LDR Brachytherapy, such as 4D Brachytherapy, mean that the treatment is now available as a one-stage implant technique that can normally be performed within 45 minutes. Improved dosimetry and clinical outcomes together with reduced side effects have been demonstrated over traditional two-stage approaches.
Saheed Rashid, Managing Director, BXTAccelyon, comments: “While the importance of men and their families researching all the treatment options available to them and discussing these with their consultant must be emphasised, there is an increasing body of evidence to suggest that, of the curative-intent treatment options, Low-Dose-Rate Brachytherapy as a mono- or combination therapy, has favourable outcomes and fewer adverse side effects.
“As a treatment, this option has been proven for over 25 years, and advancements such as 4D brachytherapy and NHS England supported toxicity barriers have further improved the patient experience.”